1. Field
The described technology relates generally to a rechargeable battery.
2. Description of the Related Art
A rechargeable battery can be repeatedly charged and discharged, unlike a primary battery that is not designed to be recharged. A rechargeable battery of a low (or small) capacity is used for small portable electronic devices, such as a mobile phone, a laptop computer and a camcorder, among other things, and a rechargeable battery of a large capacity is used as a power source for driving a motor of a hybrid vehicle or a large capacity power storage device, among other uses.
Nowadays, a high power rechargeable battery using a non-aqueous electrolyte of a high energy density has been developed, and in order to use when driving a motor of a device, for example, an electric vehicle requiring high power, the high power rechargeable battery is formed to be a large capacity battery module by coupling in series a plurality of rechargeable batteries. Such a rechargeable battery may be formed in a cylindrical shape or a rectangular (e.g., square) shape, among other shapes.
When a conductive foreign substance such as a nail or a gimlet enters from the outside of the rechargeable battery to the inside thereof, a short circuit may occur within the rechargeable battery. In this way, when a short circuit occurs, an internal temperature of the rechargeable battery may sharply increase and thus the rechargeable battery may catch fire or explode.
For example, a conductive foreign substance may enter through various directions, and the resulting heat generation level is different according to the advancing direction of the conductive foreign substance and thus it is very difficult to secure the safety of the battery.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.